spark plugs have burned out

lotsill

09-23-2007, 09:00 PM

I had a tune up on my car about a month and a half ago. About two weeks ago the car almost wanted to stall going down the road. Dropped the car at a service station, they said the spark plugs were burnt out. They replaced the plugs

On my way home tonight the same problem was occuring. When i tried to go 35 mph the car way shaking like it wanted to die.

On the orginal tune up, I know they replaced the spark plugs, spark plug wires and the distributor cap.

I was thinking maybe the igniation coil. Any ideas on what could be causing the same problem?

If it is the igniation coil, should the shop have replaced it when they did the tuneup.

Thanks

somick

09-24-2007, 12:29 PM

What brand of plugs did they put in?

As far as I know Toyota recomends NGK.

Sam

Mike Gerber

09-24-2007, 02:25 PM

"On the orginal tune up, I know they replaced the spark plugs, spark plug wires and the distributor cap."

If this is for your 1998 Carmy, it has no distributor, so it will also not have a distributor cap. To me this puts the credibility of the shop that told you they did this in question.

Is the check engine light on? If so, that would give a better indication of what system may be causing the problem. If it is on, you can take the car to Autozone. They will read the code for free. Get the code from them and report it back here. Then someone can give you some direction.

Also, it is a good idea to post which engine the car has and what mileage is currently on the car, along with any maintainance history you can give for the car.

Mike

lotsill

09-24-2007, 03:26 PM

The place that did the tuneup in February put in NGK plugs.
At tune up time they recommened getting the value cover gasket replaced, lack of funds for not replacing it.
In July I stopped at the same tuneup place and they changed the oil, they didn't mention anything about the value cover gasket.

No distributer cap, my fault.

Took it to another shop this morning they said the following.
replace the value cover gasket
replace ignitation coils
#2 was misfiring.

They then recommend replacing the wires and plugs again.

Thanks guys.

xfeejayx

09-25-2007, 11:12 AM

welcome to the AF lotsill.
need more details to help here.
what exactly do you mean by "burned out" are they all coming out black? do they have stuff on them, are they wet? more details please. Are all the plugs doing the same thing?
Do you have smoke coming out the exhaust? How often, under what conditions, and what color? is it constant or are alternating shots of colored and clear smoke? Check your oil and coolant, are either low?

ps
If you change the valve cover gasket, make sure you do the seals around the plugs also, they should be done at the same time.

also: valVe cover (not valUe), and ignition (not ignitation) coil

ProMan

09-25-2007, 11:25 AM

I doubt any of this will help you, but definitely will help them make more money.

1. Valve cover gasket : nothing to do with spark plug. It's function is to prevent oil leaking.
2. Ignition coil : it's function is to generate high voltage to initiate the spark.

Did you take a look at the burnt spark plug? What's the color around the tip? Did the tip got melted? Do you have a photo of it? Is it the spark plug on the same cylinder got burnt?

If it's the spark plug tips that got burnt out, it should be bright white. If this is the case, and it happened at the same cylinder, that cylinder has combustion problem. Then the main cause will probably your fuel injector for that cylinder.

But, if it's "burnt" electrically, then it may be the ignition coil. I don't know too much in that area. Good luck and let us know the outcome.

lotsill

09-25-2007, 05:13 PM

ProMan,

I wish you had posted 12 hours earlier, you would have saved me 300 in parts.:banghead:

Placed the following: plugs, 2 coils, wires and it still didn't resolve the problem.

Replacing the fuel injector.

xfeejayx

09-25-2007, 07:35 PM

lack of information leading to a lack of diagnosis. I don't think you mentioned anywhere that it was just one plug, would have ruled out some stuff pretty quick. in fact, you said "plugs", makes me think all went bad.

Anyway, if it is happening on all cylinders, then it's not injector (s). It might be a fuel pump, or filter. I'd replace the fuel filter first, cheap, super easy to get to, 20 minute job to replace, at least on the 4 cyl.

ProMan

09-26-2007, 10:22 AM

ProMan,

I wish you had posted 12 hours earlier, you would have saved me 300 in parts.:banghead:

Placed the following: plugs, 2 coils, wires and it still didn't resolve the problem.

Replacing the fuel injector.

Wow, hold on. You missed one step before buying the new parts. Which is testing the old ones to make sure it's the culprit. Or you maybe still wasting money and I will feel bad.

And, in most cases, the injector may just got clogged and can be cleaned. I would try some injector cleaner first. Autozone can do the test for you if the injector is off already.

The reason I suggest the injector is that if the plug got burnt at the tip, under the assumption that it happened at the same cylinder, then it implies the combustion temperature in that cylinder is way too high. Which means "lean" condition, that causes the combustion changes from "explosion" to "flash". And the casue is most possible the injector.

But if you have this problem on all cylinders, then it's something else. Good luck.